In 1971 IBM delivered a working 52-bit magnetic bubble memory chip to NASA as part of a contract investigating replacements for space-borne tape recorders.
The photos on this page show some of the hardware details. Click
here
to view the paper,
or
here
to watch a brief movie clip of the chip in action.
(Turn the sound on).

^M
^M
^M
After 7 seconds, 3 bubbles are written into the storage loop.
(Movie is rotated 180 degrees relative to the diagram.)